Essential oils and chitosan as alternatives to chemical preservatives for fish and fisheries products: A review

Meeting consumer concerns and preferences for fresh and safely processed fisheries products free of chemical and synthetic preservatives is a challenge for the aqua-food industry. As such, natural preservatives from plant and animal origin including chitosan, essential oils (EOs), plant extracts and lactic acid bacteria have attracted considerable interest recently. These preservatives have antimicrobial and antioxidant properties that can retard spoilage, uphold product quality and safety as well as extend the storage shelf-life of fish and seafood. Chitosan and EOs have been successfully used in edible coatings, film wrapping and dipping solutions. The present review focuses on the effectiveness of chitosan, EOs and other natural preservatives intended for prolonging the shelf-life of fisheries products, and maintaining their freshness and quality. Moreover, the mechanisms of action of natural additives, harmful impacts of chemical preservatives and status of aquatic food preservatives in Southeast Asian countries are summarized, with notes on important research gaps. Overall, this study informs recent development in natural preservatives related to the aqua-food industry.